If x+y+z=9, xy+yz+zx =26; find x²+y²+z²

First, we must expand  and simplify :






And Than, Enter the value :

we know,
(x + y + z)² = x² + y² + z² + 2(xy + yz + xz)
9²  = x² + y² + z² + 2 X 26
 81 = x² + y² + z² + 52       
81 - 52 = x² + y² + z²
therefore, x² + y² + z² = 29

Same length is comparing because it’s saying its the same and not different